WHAT IS POWER FACTOR OR PF – WHAT DOES kVA MEAN – WHY ARE kW DIFFERENT TO kVA – WITH WORKED EXAMPLES

In this video from LearnElectrics, we will take a very gentle look at this thing called power factor, and show you how we use Watts and volt-amperes to help us look at how efficient a system is. Starting at a nice easy level, we look at what the different terms mean and how they work together in an electrical installation.

There are always lots of questions about power factor and some of them have included things like …
How can I calculate power factor and Watts?
What is power factor and how does it affect the installation?
And why are VA and Watts different, I always thought that V times A was Watts? And now it isn’t.

But before we start on working out VA and power factor, we will have a look at some basics on the subject of waveforms and resistive and reactive circuits. All good stuff, helpful, interesting, and nice and easy to understand.

This is video number 218 and to view all our videos type in LearnElectrics all one word into the YouTube search bar.

Visit our YouTube channel where we have many more videos on a wide range of electrical topics.

[Jim]

Dave, Thanks again. I’m going to watch this a few times so I totally absorb what’s going on. As a great philosopher once said, “It is not what you know, but what you understand. I want to become an electrician who understands & you make that journey much easier for me.

[orestmushi]

Simply put. Better than an entire college course over a semester. Thank you.

[Paul-ssre]

Great tutorial, so well explained! thank you, I’m going to take a deep dive into the rest of your material

[dannysmith]

I Appreciate Learn Electrics again for this easy to comprehend presentation. Great work, thank you.

[jackeroojackeroo]

Always makes more sense the way you do it! Thank you.

[babangidaciroma]

Another smashing lesson from professor DAVE as I call him, putting in some more knowledge into our mental toolbox as usual 👌👌👏

[rajanvarghese]

The beer analogy, is quite good and a nice explanation.

[EdwardBretherton]

thanks Dave, another clearly presented lesson

[pietnel]

Great video Dave. Hope there will be a follow up video discussing the iron, copper and fixed losses that causes these inefficiencys and the ways on how to improve PF.

[bonnywail]

Another splendid and informative video..👍

[Em-PoweringElectrical]

Thank you for all your videos appreciate them all.

I also had a read on your website, extremely impressive career.

Thank you again for sharing your knowledge 🙏

[hussmortada]

Another great video, Thanks again Dave!

Have you done anything on wiring PIR and Dusk to Dawn sensors into existing circuits with switches or without etc… ? Another thing would be connections in series and parallel.

Your style of programming watching is amazing, thank you again!

[aleko_]

Thanks so much for this, absolute gold!

[malachygallagher]

Excellent as usual! Keep it going!👌
Can you do start & run capacitor sizing for motors!
Thanks mg.

[TitchgamerRG]

Love that Beer analogy Dave!
Never heard that one before haha

[HS]

Well done, thanks for taking the time to share your knowledge. Is there a formula to find the amps on that nameplate at 13:10? I can’t seem to make sense of the amperage rating on the motor?

[AngelaPeters-fytc]

Fantastic explanation Dave. Im building a house at the minute and NIE are upgrading the existing transformer from 25 KVA to 50 KVA. DOes that mean 50000 volt amperes surely thats very high unless some is lost on the overhead cables plus its feeding other properties. I assume another transformer close to the build will step that down to 230 volts or near abouts to allow for voltage drop etc. DO you have a video on how electricity gets to a house etc.

[pooley]

Hi love the videos. Always come back to your content.

Ok to ask a question tho. Client is upgrading to 3 phase from 2 phases in the application it asks for the kva. The upgrade is for 10 flats.

Where would you get the figures for the equations if you don’t know what the main fuses will be. For example if you looking to fit a 315 amp 10 way distribution GFP10.

Would you put 315 and 400 v ?

Hope that’s clear enough. Thanks again

[pdr-am]

Great video and well explained. Thank you for making these amazing videos. I just have one question. Using the motor data plate shown on the video if the voltage (400) is multiplied by current (11) equals 4.4KVA. It’s lower than the true power shown (5.5KW). I thought the apparent power is always greater than the true power. What am I missing? Thank you.

[alanmarriott]

Great video. Can I ask though I’ve come across various items and most of time they generally just show kva or Va rating so when choosing cable and breaker do you usually just work it out to that Va or Kva rating as that’s 100%? Thanks